A digital micromirror device (DMD) is a digitally controlled optical microelectromechanical system (MEMS) device. In at least one example, the DMD is a fast, reflective digital light switch. It can be combined with image processing, memory, a light source and optics to form a projector that is capable of projecting large, bright, high-contrast color images.
If an integrated circuit (IC) does not have a moving component (e.g., with mechanical operation), then the IC can be fabricated with two-dimensional or planar structures. Some MEMS fabrication techniques have been developed from integrated circuit (IC) fabrication techniques. For example, various MEMS devices have been fabricated with nominally vertical sidewalls (dry anisotropic etching), undercut sidewalls (wet isotropic etching), or sidewalls that have limited angles due to the crystallographic orientation of the substrate (wet anisotropic etching). A technique called gray-scale lithography, typically in diffractive optics, may be applied using a one level development process to create three-dimensional (3D) structures in photoresist.